New load_screen_** action

[aussieguy123]

WordPress includes a load-<page> hook, however this is not specific enough to have a function that runs only on one single screen in the admin area without additional logic. Lets say I have a custom post type "killed_attachment" and I want to have a function which will only run on the edit posts screen for this post type.

My proposed solution:

<?php
/**
 * Fire load_screen_* hooks
 * @action admin_init (or a better action, suggestions?)
 */
 public function run_load_screen_hooks() {
        $current_screen = function_exists( 'get_current_screen' ) ? get_current_screen()->id : null;
        do_action('load_screen_' . $current_screen);
 }

With this new action, instead of requiring logic to detect the screen as in:

<?php
        /**
         * @action admin_init
         */
        public function run_on_killed_attachments_edit_post_only() {
                $current_screen = function_exists( 'get_current_screen' ) ? get_current_screen()->id : null;

                switch ( $current_screen ) {
                        case 'edit-killed_attachment':
                                //Code which will only run on the killed attachment edit posts screen 
                                break;
                        default:
                                break;
                }
     }

You could simplify this as:

<?php
        /**
         * @action load_screen_edit-killed_attachment
         */
        public function admin_enqueue_scripts() {
            //Code which will only run on the killed attachment edit posts screen 
        }

Basically both functions do the same thing but one is 9 lines long and contains extra logic, the other is one line long.

Shorter functions and less logic means less bugs and more readable + maintainable code.

[westonruter]

@aussieguy123 thanks for the ticket. There is actually a ​current_screen action that currently triggers. It seems like you're essentially suggesting a current_screen_{$screen_id} action?

[aussieguy123]

Yes. I saw the existing current_screen hook. However that would also need extra logic in code hooked into it to have code run on a specific screen. So this is a new load_screen_{$screen_id} action

Perhaps the code to set up this new action could be hooked into the existing current_screen action?

Something like:

<?php
add_action( 'current_screen', function() {
       $current_screen = function_exists( 'get_current_screen' ) ? get_current_screen()->id : null;
       do_action('load_screen_' . $current_screen);
});

[DrewAPicture]

Looking at your examples, I'm not really sure what the advantage to a new dynamic hook would be other than making what is already pretty straightforward with current_screen slightly more specific.

As pointed out, the existing current_screen hook could be used for what you want, and the screen object is passed to it:

<?php
add_action( 'current_screen', function( $screen ) {
    if ( isset( $screen->id ) && 'killed_attachment' === $screen->id ) {
        // Do stuff.
    }
} );

[aussieguy123]

@DrewAPicture the idea of the action is to avoid the need for the if statement (or other logic) whenever you want something to run on a specific admin screen.

This is similar to how alot of MVW style frameworks work, instead of using an if statement to detect a page they would use something else (like a route or action) to hook into the page directly.

With the screen passed to current_screen, the code to set up this new action could be as simple as:

<?php
add_action( 'current_screen', function( $screen ) {
   do_action( 'load_screen_'.$screen->id );
} );

These 3 lines would save alot of if statement lines

[DrewAPicture]

@aussieguy123 I understand your use case – I'm saying that don't think that reason alone is adequate justification for adding a new dynamic hook in this context.

Thank for you the suggestion and your willingness to submit a patch for consideration, however, I'm going to close this ticket was wontfix. If a greater need for such a hook should arise in the future, we can certainly reopen this ticket to revisit it.